The disclosure of my earlier patent, U.S. Pat. No. 5,878,155, issued Mar. 2, 1999 is incorporated herein by reference. In U.S. Pat. No. 5,878,155 at column 2, lines 40-42, the possibility employing temporary tattoos for the verification method disclosed therein is disclosed. The present invention in a preferred embodiment provides a further security improvement by employing a series of temporary tattoos, each valid only for a temporary period of time. The tattoos and the time periods are each predetermined, which makes unauthorized use very difficult to occur in the first instance; however, should an unauthorized use occur, it is very unlikely to persist for long because the tattoo information would change frequently. Moreover, in the situation where the tattoo was changed daily, reporting a “lost” card would rarely be needed because of the automated frequency of the tattoo code changes.
By analogy, the temporal aspect of the invention is like two people (the bank and its customer) following a private musical composition that only the two of them know by heart, and therefore only the two of them will know what musical note comes next in the sequence: Conceptually analogous security measures are taken by the United States military vis a vis military personnel's use of frequency hopping radio transceivers—where only the sender and receiver have prior knowledge and access to the common secure frequency sequence used as part of a single secure communication.
Finally, the temporal sequence of tattoos markings themselves need not follow any logically sequential pattern, and in fact they ideally would not follow recognizable visual sequence so that random guessing of the next tattoo in the sequence would be virtually impossible for an outsider to do.